TidyTuesday Link

https://github.com/rfordatascience/tidytuesday/blob/master/data/2021/2021-07-20/readme.md

 

Droughts_in_the_United_States

Dry and wet cycles are dependent on a number of factors including geography, topology and climate drivers. Drought phases in the US can be explained by changes in the track of extratropical cyclones, which can occur during climate cycles such as the El Niño-Southern Oscillation, or ENSO, as well as the North Atlantic Oscillation, Pacific Decadal Oscillation, and Atlantic multidecadal oscillation. The country’s contiguous western and especially southwestern region has experienced widespread drought since about year 2000 (https://en.wikipedia.org/wiki/Droughts_in_the_United_States).

 

Data

2001-2021 US droughts data are collected by the US Drought Monitor.

The U.S. Drought Monitor is jointly produced by the National Drought Mitigation Center at the University of Nebraska-Lincoln, the United States Department of Agriculture, and the National Oceanic and Atmospheric Administration. Map courtesy of NDMC.

 

Data sample

map_date state_abb valid_start valid_end stat_fmt drought_lvl area_pct area_total pop_pct pop_total drought_desc
20210713 AK 2021-07-13 2021-07-19 2 None 74.35 433133.2 33.91 240644.2 no drought
20210713 AK 2021-07-13 2021-07-19 2 D0 25.65 149435.1 66.09 468985.8 abnormally dry
20210713 AK 2021-07-13 2021-07-19 2 D1 0.00 0.0 0.00 0.0 moderate drought
20210713 AK 2021-07-13 2021-07-19 2 D2 0.00 0.0 0.00 0.0 severe drought
20210713 AK 2021-07-13 2021-07-19 2 D3 0.00 0.0 0.00 0.0 extreme drought
20210713 AK 2021-07-13 2021-07-19 2 D4 0.00 0.0 0.00 0.0 exceptional drought
20210706 AK 2021-07-06 2021-07-12 2 None 74.35 433133.2 33.91 240644.2 no drought
20210706 AK 2021-07-06 2021-07-12 2 D0 25.65 149435.1 66.09 468985.8 abnormally dry
20210706 AK 2021-07-06 2021-07-12 2 D1 0.00 0.0 0.00 0.0 moderate drought
20210706 AK 2021-07-06 2021-07-12 2 D2 0.00 0.0 0.00 0.0 severe drought
20210706 AK 2021-07-06 2021-07-12 2 D3 0.00 0.0 0.00 0.0 extreme drought
20210706 AK 2021-07-06 2021-07-12 2 D4 0.00 0.0 0.00 0.0 exceptional drought

 

Drought levels

levels labels
None no drought
D0 abnormally dry
D1 moderate drought
D2 severe drought
D3 extreme drought
D4 exceptional drought

 

 

States affected by “extreme drought” (D3) or “exceptional drought” (D4)